hdMolluscidin is an antimicrobial peptide consisting of 46 amino acids with a molecular weight of 4767.2 Da, purified from the gill of abalone (Haliotis discus). It is an antimicrobial peptide which exhibits little hemolytic activity and exhibits strong antimicrobial activity against Gram positive and Gram negative bacteria but no activity against C. albicans. In order to overcome the limited activity of hdMolluscidin and the limitation caused by the length of 46 amino acids, it is necessary to design and develop a new antimicrobial peptide such as an analogue with a fragmented length and increased antimicrobial activity.
According to recent studies, it is reported that the antimicrobial peptide plays an important role as one of effective defense mechanisms against external sources of infection in the gill and mantle of oyster and sea mussel. This result suggests that the gill and mantle are organs which play an important role in the immune mechanism of shellfish, as a primary defense against external environments, and they are important targets in the search and purification of substances having antimicrobial activity. However, there has not been much effort in developing novel antimicrobial peptides therefrom.
Korean Patent Registration No. 10-1384578 (patent document 1) relates to an antimicrobial peptide having a novel amino acid sequence, more particularly to an antimicrobial peptide isolated from abalone, which has antimicrobial activity against E. coli or Staphylococcus aureus. However, the patent document 1 does not disclose an antimicrobial peptide analogue derived from abalone which is commercially viable because it is composed of 15 or less amino acids and exhibits stronger antimicrobial activity against various bacteria.